var pet = {

	words : '...',
	speak: function(say){
	
		console.log(say +　' ' + this.words );
	}
}
// pet.speak('Speak');

// dog拥有了pet的技能，利用这一点可以实现继承
var dog = {
	words:'Wang'
}

pet.speak.call(dog,'speak'); 